This invention relates to disposable containers having covers and particularly to such a container wherein the cover is releasably interlocked with the container by "snap-lock" closure means.
In the use of covered containers to package, distribute and display bakery goods such as cakes, it is desirable that the cover be of a transparent material to permit visual inspection of the cake within the package. Therefore, and since the package is intended to be disposable, the cover is normally formed of a see-through plastic material. Securement of the cover to the container can be achieved by heat sealing, sealing tape or stapling, although these types of closures are relatively expensive. A less expensive closure can be achieved by forming the cover to provide a depending flange to "snap-over" the rim of the underlying container, although this usually results in a loose or otherwise ineffective closure.
The inexpensive "snap-over" closure is considered a desirable closure because of the simplicity involved in effecting the interlock between the cover and container. Basically, all that is required is placing the cover on the container and exerting downward pressure on the cover, However, the resultant closure is still a loose-fitting and ineffective closure. The cause of the loose-fitting closure is believed to be the movement of the container side and end walls inwardly and away from the cover flange due to downwardly flexing of the container bottom wall resulting from the weight of the cake in the container.
Accordingly, it is the primary object of this invention to provide a "snap-lock" type of closure for locking a cover to a container in a manner that would result in an effective, close fitting interlock between the cover and the container.